Automatic backwash filter control



. J. P. LAWLJOR 2,184,618

AUTOMATIC BACKWASH FILTER CONTROL Dec. 26, 1939.

Filed Nov. 15, 1957 IN VENTOR.

11.1 LFIWLEIH 7W ATTORNEY.

Patented Dec. 26, 1939 UNITED STATES PATENT OFFICE,

6 Claims.

The principal object of my invention is to provide an apparatus for usein combination with filters and the likethat will automatically causethe filter to be backwashed for eliminating accumulated impurities inthe filter after the filter has collected and retained a predeterminedamount of impurities.

A further object of this invention is to provide an automatic backwashfilter control apparatus that permits adjustment as to the duration ofthe backwashed time.

A still further object of my invention is to provide an automaticapparatus for controlling the flow of the fluid in both directionsthrough a filter that is highly efiicient in operation, economical inmanufacture and durable in use.

These and other objects will be apparent to those skilled in the art.

My invention consists in the construction, arrangement and combinationof the various parts of the device, whereby the objects contemplated areattained as hereinafter more fully set forth, pointed out in my claimsand illustrated in the accompanying drawing, in which:

Fig. 1 is a side view of my complete apparatus installed and ready foruse.

Fig. 2 is a front view of my device and more fully illustrates itsconstruction.

As is well known, filters become clogged and fouled from use and it isnecessary to backwash them from time to time to maintain any worthwhileefficiency. It is quite easy to cause the backwashing of filters bymanual manipulation of valves or by predetermined timing devices thatwill periodically cause the filter to be backwashed. Obviously, however,a filter may quickly accumulate impurities or it may require aconsiderable length of time to accumulate sufiicient impurities before abackwash is needed. With automatic timing devices or by manual operatedmeans, filters may need cleaning long before they are backwashed, or onthe other hand may not need cleaning at the time they are backwashed. Ihave overcome such objections by providing a non-complicated apparatusfor use in combination with filters that will automatically cause thefilter to be backwashed at the moment a predetermined amount of sludgeor impurities have been accumulated in the filter.

Referring to the drawing, I have used numeral Hi to designate inconventional form an ordinary filter having an inlet pipe llcommunicating with its inside top and an outlet pipe l2 communicatingwith its inside bottom. By the construction and arrangement of partsshown in my drawing, this pipe 12 is designed to lead to an elevatedsupply tank such as a stand pipe or other means for maintaining fiuidunder pressure inside the pipe l2 regardless of the direction of fiow'ofthe fluid through the filter. I have used the numeral l3 to designatethe frame portion of my device. The numeral M designates a tank securedto the upper portion of the frame 13 and resting in a horizontal plane.The numeral l5 designates a shaft rotatably extending through the rearside portion of the tank M as shown in Fig. 1. The numeral IE'designatesmy upper tipping tray rigidly secured by any suitable means at its rearbottom end to the shaft l5. This tipping tray l5 has its rear lower endwithin the tank l4 and when in normal upright position as shown in Fig.1 has its bottom extending upwardly and forwardly. The numeral [6designates an outlet port in the bottom of the tipping tray [5 near itsforward bottom end. The numeral l1 designates a liquid receiving andguiding cup flange on the rear top end of the tray 15 and communicatingwith the inside of the tipping tray. The numeral [8 designates a stop inthe forward end portion of the tank M 'for limiting the downwardmovement of the forward end of the tray 15 within the tank [4 when thetray is moved to a lowered position as shown by dotted lines in Fig. 1.When the tray I5 is in such lowered position, its bottom will besubstantially horizontal. The numeral 19 designates a shaft rotatablymounted in the frame I3 and positioned in a plane directly below theplane of the shaft 15'. The numeral 20 designates my second tipping traywhich is an exact duplicate I of the tipping tray 15. This tray 20 alsohas an outlet port 2| and a liquid receiving and guiding element 22. Therear lower end of this second tray 29 is rigidly secured by any suitablemeans to'the shaft 19. The numeral 23 designates an arm rigidly securedat one end to the shaft l5 and extending forwardly. The numeral 24designates a similar arm rigidly secured at one end to the shaft I 9 andextending rearwardly. When the trays l5 and 2!! are in elevatedpositions, their arms 23 and 24 extend horizontally. The numeral 25designates a link rod having one end pivoted to the free end of the arm23 and its other end pivoted to the free end of the arm 24. The lengthof this rod arm 25 is such that when the tipping tray I5 is in elevatedposition, the arm 23 will be in a horizontal position and the tippingtray 2|! will be in a lowered position and the arm 24 will extendupwardly and rearwardly. Likewise when the tray I5 is in a loweredposition the arm 23 will extend downwardly and forwardly and the tippingtray 28 will be in an elevated position and the arm 24 will be in ahorizontal plane. The numeral 26 designates a manually adjustable valvecommunicating with the inside rear bottom of the tank I 5 and capable ofemptying directly into the portion 22 of the tray 28 when the tray 28 isin an elevated position as shown by dotted lines in Fig. 1. The numeral2i designates a drain pipe having a funnel 2% for receiving liquiddirectly from. the outlet opening 2| of the tray 28 when the tray 23 isin a lowered position. The numeral 29 designates a pipe communicatingwith the inside of the waste pipe 21. The numeral 30 designates a funnelon the outer end of the pipe 29 located directly below the valve 26 andbelow the portion 22 of the tray 20 when the tray 20 is in an elevatedposition. The numeral 3i designates a vertical pipe communicating withthe inside top of the filter l0 and discharging at a point directlyabove the portion ll of the tray 55 when the tray i5 is in an elevatedposition. This pipe 3! extends to an elevation substantially above thefilter iii and has embossed in its length an ordinary adjustableyielding valve 32 shown in conventional form in Fig. 1. This valve 32yieldingly closes communication between the inside of the pipe 2! andthe inside of the filter ill. The numeral 33 designates an ordinaryfour-way valve shown in conventional form and having its operating rodrigidly secured to the rear end of the arm 24. The numeral 34 designatesthe waste water pipe communicating with the inside of the four-way valve33. The numeral designates the fluid inlet pipe designed to be incommunication with a source of liquid under pressure. In generalpractice, this pipe 35 may be connected with and communicate inside withthe pipe ii any point previous of the gate valve 36 imposed in the pipeH. The numeral 3'! designates a pipe having one end communicating insidewith the pipe II at a point past the gate valve 36 and its other endcommunicating inside with the drain pipe 2?. The numeral 38 designates agate valve imposed in the pipe 3'? and arranged diametrically oppositefrom the gate valve 36 as shown in Fig. 1. The numeral 3Q designates acylinder positioned between the gate valves 36 and 38. The numeral 46designates a shaft extending completely through the enclosed cylinder 39and connected to the gate valves 38 and 38. The numeral 4| designates apiston rigidly secured to the shaft 48 and positioned inside thecylinder 39. The numeral 42 designates a pipe having one endcommunicating with the inside of the four-way valve 33 and its other endcommunicating with the inside of the cylinder 39 and one side of thepiston 6!. The numeral 43 designates a second pipe communicating the oneend with the inside of the four-way valve 33 and its other endcommunicating with the inside of the cylinder 39 at a point on the otherside of the piston H.

The practical. operation of this device is as follows:

Normally water or other liquid will pass through the open gate valve 3%,pipe l l and into the filter Hi from which it will flow through the pipel2. After the filter begins to accumulate sufficient impurities toimpair its efiiciency, head pressure will be accordingly built up withinthe upper portion of the filter thereby opening the valve 32 and risingand passing from the pipe 3i into the tipping tray l 5. Obviously thegreater amount of collected impurities inside the filter, the greaterwill be the head pressure and any desired moment of backwashing relativeto the amount of accumulated impurities may be had by adjusting theadjustable pressure valve 32. In some cases it may be desirable todispense with the valve 32 entirely andthe increased head pressurewithin the filter caused by impurities will cause the water to risewithin the pipe 3| and into the tray l 5. When sufiicient water has beendisposed within the tipping tray l5, it will become overbelanced at itsforward end and will automatically and quickly fall to a horizontalposition as shown by dotted lines in Fig. l. Considerable quantity ofwater must be in the tray before it does move to a lowered position andwhen it once starts to such lowered position, its movement will be rapidand definite due to its sloping bottom approaching a horizontalposition. Due to the linkage between the tray I5 and the tray 26, thedownward movement of the tray l 5 will raise the empty lower tray 20 toan elevated position. With the tray l5 in a lowered position, thecollected water will pass through the opening it and into the tank Hi.From the tank Hi the water will pass through the valve 2% into the tray20. Up to the downward movement of the tray 15 the gate valve 36 will beopen and the gate valve 38 closed. The four-way valve will be sopositioned that the pipe 35 will be in communication with the upper endof the cylinder 39 and the pipe 43 will be in communication with thedrain outlet pipe 34. However upon the movement of the tray 55 to adownward position, the four-way valve 33 will be changed and the pipe 35will be in communication with the lower end of the cylinder 33 and thepipe d2 will be in communication with the drain outlet pipe 154. Withwater under pressure below the piston 6| the gate valve 35 will beclosed and the gate valve 38 opened. By the pipe 82 being incommunication with the pipe 34, the water above the piston may escape asthe piston moves upwardly. With the gate valve 36 closed and the gatevalve 3.; opened, the water or other liquid being purified will reverseits flow, pass downwardly through the pipe l2 into the bottom of thefilter. From the bottom of the filter it will pass upwardly and outthrough the open gate valve 38 to the drain pipe 21 to backwash thefilter. As soon as sufiicient water has passed from the tank M into thetray 20, the tray 28 will move to a lowered position thereby raising thetray l5 to its normal upright position. This reverses the four-way valve33 and water under pressure will pass into the upper portion of thecylinder 39 thereby forcing the piston ll downwardly to open the gatevalve 36 and close the gate valve 38. The pipe 43 will be incommunication with the pipe 3Q to permit the escape of water below thepiston ll. At this time the filter will assume its normal operation.When the tray 2B is in lowered position, collected water will pass fromit into the funnel 28. Any continued drippings from the valve 26 willfall into the funnel 30. The length of time of the backwash will dependupon the length of time for suflicient water to pass into the tray 20and tip it. This time element may be adjustably controlled by themanually operated valve 26.

Some changes may be made in the construction and arrangement of myimproved automatic backwash filter control without departing from thereal spirit and purpose of my invention, and it is my intention to coverby my claims any modified forms of structure or use of mechanicalequivalents which may be reasonably included within their scope.

I claim:

1. In a control apparatus, a frame, a tank secured to said frame, atipping tray pivotally supported at one of its lower ends above thebottom of said tank, an outlet passageway in said tipping tray capableof directing a liquid into said tank when said tipping tray is in alowered tipped position, a, second tipping tray pivotally supported atone of its lower ends below the bottom of said tank, an outletpassageway in said second tipping tray capable of directing liqu d fromsaid second tipping tray when said second tipping tray is in a loweredtipped position, an arm operatively rigidly secured to said mentionedtipping tray, an arm operatively rigidly secured to said second tippingtray, a connecting member having one end pivotally secured to said firstmentioned arm and its other end pivotally secured to said last mentionedarm, an operating shaft operatively connected to one of said arms, anoutlet passageway in said tank capable of directing liquid into saidsecond mentioned tipping tray when said tipping tray is in an uprightposition, and a means terminating above sa d first mentioned tray whensaid tray is in an upright position for furnishing a liquid to saidfirst mentioned tray.

2. In a control apparatus a frame, a tank secured to said frame, atipping tray pivotally supported above the bottom of said tank capableof being overbalanced when a liquid is placed in it and moved from anupright position to a lowered tipped position. an outlet passageway insaid tipping traycapable of directing liquid within it into said tankwhen said tipping tray is in a lowered tipped position, a second tippingtray pivotally supported below the bottom of said tank capable of beingmoved to a lowered tipped position from an elevated position when liquidis placed in it, an outlet passageway in said second tipping traycapable of directing liquid from said tray when said tray is in alowered position. an arm operatively rigidly secured to said tippingtray extending in a horizontal plane when said tipping tray is in anelevated position, an arm operatively rigidly secured to said secondtipping tray extending in a horizontal plane when said tipping tray isin an elevated position, a connecting member having one end pivotallysecured to said first mentioned arm and its other end pivotally securedto said last mentioned arm, an operating shaft operatively connected toone of said arms, an outlet passageway in said tank capable of directingliquid into said second mentioned tipping tray when said tipping tray isin an upright position, and a pipe capable of furnishing a liquid tosaid first mentioned tray when said first mentioned tray is in anupright position.

3. In a control apparatus a frame, a tanksecured to said frame, atipping tray pivotally supported above the bottom of said tank capableof being overbalanced when a liquid is placed in it and moved from anupright position to a lowered tipped position, an outlet passageway insaid tipping tray capable of directing liquid within it into said tankwhen said tipping tray is in a lowered tipped position, a second tippingtray pivotally supported below the bottom of said tank capable of beingmoved to a lowered tipped position from an elevated position when liquidis placed in it, an outlet passageway in said second tipping traycapable of directing liquid from said tray when said tray is in alowered position, an arm opera' tively rigidly secured to said tippingtray extending in a horizontal plane when said tipping tray' is in anelevated position, an arm operatively rigidly secured to said secondtipping tray extending in a horizontal plane when said tipping tray isin an elevated position, a connecting member having one end pivotallysecured to said first mentioned arm and its other end pivotally securedto said last mentioned arm, an operating shaft operatively connected toone of said arms, an adjustable outlet passageway in said tank capableof directing liquid into said second mentioned tipping tray when saidtipping tray is in an upright position, and a means terminating abovesaid first mentioned tray when the same is in an upright position forfurnishing a liquid to said first mentioned tray when the same is in anupright position. i

' 4. In a control apparatus, a frame, a tank secured to said frame, atipping tray pivotally supported at one of its lower ends above thebottom of said tank, having its bottom extending upwardly and outwardlywhen it is in an elevated position, a liquid supply pipe terminatingabove said tray when said tray is in an elevated position; said supplypipe designed to be in communication with the inside top of a liquidcontainer, an outlet passageway in said tipping tray capable ofdirecting a liquid into said tank when said tipping tray is in a loweredtipped position, a second tipping tray pivotally supported at one of itslower ends below the bottom of said tank, having its bottom extendingupwardly and outwardly when it is in an elevated position, an outletpassageway in said second tipping tray capable of directing liquid fromsaid second tipping tray when said second tipping tray is in a loweredtipped position, an arm operatively rigidly secured to said mentionedtipping tray, an arm operatively rigidly secured to said second tippingtray, a connecting member having one end pivotally secured to said firstmentioned arm and its other end piv- I otally secured to said lastmentioned arm a liquid supply pipe designed to be in communication withthe inside of a liquid container, an operating shaft operativelyconnected to one of said arms, a multipassageway valve connected to saidshaft and imposed in said last mentioned liquid supply pipe.

5. In combination with a filter having inlet and outlet pipes, a controlapparatus comprising a frame, a tank secured to said frame, a tippingtray pivotally supported at one of its lower ends above the bottom ofsaid tank, having its bottom extending upwardly and outwardly when it isin an elevated position, an outlet passageway in said tipping traycapable of directing a liquid into said tank when said tipping tray isin a lowered tipped position, a second tipping tray pivotally supportedat one of its lower ends below the bottom of said tank, having itsbottom extending upwardly and outwardly when it is in an elevatedposition, an outlet passageway in said second tipping tray capable ofdirecting liquid from said second tipping tray when said second tippingtray is in a lowered tipped position, an arm operatively rigidly securedto said mentioned tipping tray, an arm operatively rigidly secured tosaid second tipping tray, a connecting member having one end pivotallysecured to said first mentioned arm and its other end pivotally securedto said last mentioned arm, valves imposed in said filter inlet pipe, anoperating shaft connected to one of said arms operatively connected tosaid valves in said inlet pipe for causing the opening and closing ofthe top of said filter and terminating above said first mentionedtipping tray when said tipping tray is in an elevated position.

6. In combination with a filter having inlet and outlet pipes, a controlapparatus comprising a frame, a tank secured to said frame, a tippingtray pivotally supported at one of its lower ends above the bottom ofsaid tank, having its bottom extending upwardly and outwardly when it isin an elevated position, an outlet passageway in said tiping traycapable of directing a liquid into said tank when said tipping tray isin a lowered tipped position, a second tipping tray pivotally supportedat one of its lower ends below the bottom of said tank, having itsbottom extending upwardly and outwardly when it is in an elevatedposition, an outlet passageway in said second tipping tray capable ofdirecting liquid from said second tipping tray when said second tippingtray is in a lowered tipped position, an arm operatively rigidly securedto said mentioned tipping tray, an arm operatively rigidly secured tosaid second tipping tray, a connecting member having one end pivotallysecured to said first mentioned arm and its other end pivotally securedto said last mentioned arm, valves imposed in said filter inlet pipe, anoperating shaft connected to one of said arms operatively connected tosaid valves in said inlet pipe for causing the opening and closing ofthe same, a pipe communicating with the inside top of said filter andterminating above said first mentioned tipping tray when said tippingtray is in an elevated position, and an adjustable pressure actuatedvalve imposed in said last mentioned pipe.

JOSEPH P. LAWLOR.

